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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
  1. GRB 060712: XRT refined analysis
  2. GRB 060712: Swift/UVOT Upper Limits
  3. GRB060526: optical observations
  4. GRB 060712: XRT refined position
  5. GRB 060712: Refined analysis of the Swift-BAT burst
  6. GRB060712: MASTER optical observation
  7. GRB120706: MASTER optical observation
  8. GRB 060712: Swift detection of a burst
  9. Host galaxy of GRB050904: 250 GHz upper limit with MAMBO at the IRAM 30m
  10. GRB 060708: PROMPT Optical Limits
  11. GRB 060707: OA fading and redshift
  12. GRB 060708: Swift-XRT refined analysis
  13. GCN 060708: Swift-UVOT Observations
  14. GRB 060708: Refined analysis of the Swift-BAT burst
  15. GCN 060707: Swift-UVOT observations
  16. GRB 060707: Swift-XRT refined analysis
  17. GRB 060708: Swift detection of a burst with an UVOT countpart
  18. GRB060707 possible optical confirmation
  19. GRB 060707: BOOTES-IR optical afterglow candidate
  20. GRB 060707: Refined analysis of the Swift-BAT burst
  21. GRB 060707: BOOTES-IR optical observation
  22. GRB060614: Possible SN Bump in UVOT U Band Light Curve
  23. GRB 060707: Swift detection of a burst
  24. GRB 060515: Upper Limit on Host Galaxy
  25. GRB 050223: Magellan redshift
  26. GRB 060614: SMARTS host galaxy observations
  27. GRB 060614: Detection of a Possible, Late-Time Rebrightening
  28. Correction to GCN 5278 & GCN 5279 (GRBs 060105 & 060109)
  29. GRB 060109: Upper Limit on Host Galaxy
  30. GRB 060105: Upper limit on Host Galaxy
  31. GRB060614: Detection of the host galaxy but no supernova emission
  32. GRB 060614: redshift confirmation
  33. GRB 060614: Redshift
  34. Swift-BAT trigger 215279 is not a GRB
  35. Trigger 215279: Swift detection of a possible burst (GRB 060619)
  36. GRB060614: Optical observations
  37. GRB 060614: spectroscopy
  38. GRB050326: Host Galaxy Candidates
  39. GRB050124: Possible Host Galaxy
  40. GRB050223: Host Galaxy
  41. GRB060512: near IR observations
  42. GRB060526: optical observations
  43. GRB 060614: pseudo-z from spectral parameters of the prompt emission
  44. Konus-Wind observation of GRB 060614
  45. GRB060605: optical observation
  46. The Unusually Long-Lived Afterglow of GRB 060614
  47. GRB 060614: optical observations
  48. GRB 060605, optical observations
  49. GRB 060614, SMARTS optical/IR afterglow observation
  50. GRB060614: SSO 1m observations
  51. GRB060614: Watcher observation
  52. GRB 060614: Swift-BAT refined analysis
  53. GRB 060614: Swift/UVOT Observations
  54. GRB060614: Swift-XRT refined analysis
  55. GRB 060604, optical observations
  56. GRB 060614: Swift detection of a burst with a bright optical and X-ray counterpart
  57. GRB 060602A: Swift/XRT analysis
  58. BAT Trigger #214277 is SGR 1900+14
  59. GRB 060610: KAIT observations
  60. GRB 060607: RTT150 optical observations
  61. GRB 070706B: Watcher upper limit
  62. GRB 060607B: Swift-BAT Refined Analysis
  63. GRB060602A: Swift/UVOT upper limits
  64. GRB 060607B: Swift detection of a burst
  65. GCN 060607: Swift-UVOT obswervations.
  66. GRB 060607: Swift-BAT Refined Analysis
  67. GRB 060607: optical limit by "Pi of the Sky"
  68. GRB 060607: Swift-XRT Team refined analysis
  69. GRB 060607: IR observations
  70. GRB 060502B: A Bright Early-type Galaxy as Putative Host of the Short Burst
  71. VLT/UVES observations of GRB 060607
  72. GRB 060607: PROMPT Observations
  73. GRB 060605: RTT150 optical observations
  74. GRB 060607: REM NIR afterglow
  75. GRB 060607: Swift detection of a burst with bright optical counterpart
  76. GRB 060522: PROMPT Optical Limits
  77. GRB 060605 BAT refined analysis
  78. GRB 060605: Xinglong TNT optical observations
  79. GRB060602B : REM infrared observations
  80. GRB060605: Swift/UVOT detections
  81. GRB 060605: Swift-XRT Team refined analysis
  82. SALT spectroscopy of GRB 060605
  83. GRB 060605: TNG optical observations
  84. GRB 060605: RTT150 optical observations
  85. GRB060605: Spectral Observations and Redshift
  86. GRB 060605: ROTSE-III Optical Counterpart
  87. GRB 060605: Swift detection of a burst with optical counterpart
  88. GRB 060605: ROTSE-III Detection of Optical Counterpart
  89. GRB060604: Swift/UVOT detections
  90. GRB 060604: redshift
  91. GRB 060512: Keck Redshift
  92. GRB 060604 optical photometry
  93. GRB 060604: Swift-XRT Team refined analysis
  94. GRB 060604: BAT refined analysis
  95. GRB 060604A: ROTSE-III Optical Limits
  96. GRB 060604: Swift detection of a burst with possible optical counterpart
  97. GRB 060602A: Swift-BAT Refined Analysis: Correction
  98. GRB 060602B: XMM-Newton Survey Source
  99. GRB 060602B: Swift-XRT Refined Analysis
  100. GRB 060602B: Swift-BAT Refined Analysis

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